Coal cutter



J. R. LAWSON Jan.' 3, 1933.

COAL CUTTER Filed March 2l, 1931 2 Sheets-Shee Jan. 3, 1933. J. R. LAWSON 1;@92844 COAL CUTTER Filed March 2l, 1931 2 Sheets-Sham 2 Patented `lan. 3, 1933 JOI-IN R. LAWSON, OF DENVER, COLORADO COAL CUTTER Application led March 21, 1931. Serial No. 524,354.

cleanly when reciprocated across a coal seam in the manner of a saw. t

A further object of the invention is to provide a new and novel cutting unit by means of which a coal vein may be easily and rapidly cut and which may be adjusted within certain limits to regulate the size of the kerf formed in the coal seam.

A still further object of the invention is'to provide a cutting unit which may be readily o coupled with other units of the same character so that a gang thereof may be reciprocated across a coal vein and in which a plurality of teeth are formed which are detachably secured in position in a novel manner.

Other objects and advantages ofthe present invention will become apparent as the description of the same proceeds,'and the invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with the understanding, however, that the invention is not conned to any strict conformity with the showing of the drawings but may be changed or modified so long as such changes or modifications mark no-material departure fro-m the salient features of the invention as expressed in the appended claims.

In the drawings Figure l shows the manner in which the present method of removing coal seams from pillars, located between rooms or entries, is carried out, using theJ particular form of cut- ,45 ter element constituting one of the features of the present invention.

Figure 2 is a view of one of the cutter elements partially in longitudinal section and a portion of a second cutter element, showing the connecting means between the two.Y

Figure 3 is a sectional view taken on the line 3 3 of Figure 2.

Figure 4 is a view in front elevation of a cutter unit from which the teeth have been 'out the several views, the cutter unit forming a part of the present invention is indicated 6 generally by the numeral l, Figure l of the drawings illustratingthe manner in which a number of these units are connected together for cutting through a pillar. The pillar in this view is indicated by the numer- G al 2. and the entrance or galleries surrounding it are indicated by the numerals 3.

- In carrying out the present method of removing a seam of coal from the pillar, a number of the cutting units l are connected togetherby the bars 4, as will be hereinafter more specifically described, and each of the end units has one Vof these bars 4 attached thereto to facilitate the connection with the 7 end units of the cables 5.

The group of cutter units is disposed across the pillar 2 and at each'side of the pillar there is placed in the entry or gallery 3 adjacent thereto a post 6 to which is connected, by 8 means of a suitable chain or cable 7, a pulley block 8. Each of the cables 5 is run through the adjacent pulley block and it is then carried .along the entry 3 in which it is located to the cross connecting entry at the side of the pillar remote from the side upon which the cutters l are located. Suitable posts 9 are disposed at the said opposite side of the pillar 2, adjacent the corners thereof, to which pulley blocks l0 are attached and through which 90 the cables 5 run to make a right angled turn for connection with one of a pair of drums ll operated by a suitable mechanism l2, by means of which they may be rotated in unison so that as one is winding up lthe cable attached thereto the other will be paying out the Vcable wound thereabout.

The mechanism 12 is also of the proper character to facilitate reversing the direction of rotation of the drums at the proper intervals so that the gang of cutters 1 will be dragged back and forth, in the nature of a. cross cutting saw, across the coal seam in the pillar.

Referring now to Figures 2 to 4 inclusive, it will be seen that the cutter unit 1 cornprises a flat body having an elongated head 13 from the back of which there extends the integral portion 14 of reduced thickness, the edges of which are cut to converge rearwardly, as illustrated in Figure 2. A rear edge 15 of the portion 14 extends substantially parallel with the front of the head 13 and each face of the portion 14 has projecting therefrom a flange 16 which parallels this edge. These flanges 16 serve as runners to support the back of the cutter when the same is in working position, that is, when it is lying flat upon one side.

Extending longitudinally through the head 13, and opening through each end thereof, is a passage 17 which extends into, and is of reduced width in, the reduced portion 14, as indicated at 18. The reduced portion 14 of the cutter has a series of apertures 19 formed transversely therethrough, which apertures, of course, pass through the reduced part 18 of the passage through the head.

The face of the head is formed to provide the three surfaces shown in Figure 3, the central surfa ce 2O being in a plane at right angles to the sides of the head while at each side thereof is a beveled surface 21 which extends in a plane oblique to the sides of the head.

At the opposite sides of the transverse center of the head 13 there are formed the recesses 22 and adjacent each of these recesses and between the same and the transverse lcenter of the cutter is a socket 23 which is formed in the center surface 20 and extends through the head into the passage 17. In each of these recesses 23 is positioned a cutter tooth 24 which projects, as shown in Figure 8, from the central surface 20 at right angles thereto. The wall of each recess nearest. the adjacent socket 23 is provided with a threaded bore 25 which opens into the socket and which receives a set screw 26 which, as shown .in Figure 2, engages the adjacent tooth 24 to secure it in position.

Adjacent each end of the cutter head there is formed a pair of sockets, each of which is indicated by the numeral 27 and these sockets, as shown in Figures 8 and 4, are formed in the oblique surfaces 21 of the head, one being in one surface and one in the other, as illustrated, and each extends through into the passage 17. Each of these sockets 27 receives a tooth 28 and, as the sockets are disposed at an oblique angle in the head with respect to the side faces thereof, it will be readily seen that the teeth therein will be directed laterally, as illustrated in Figure 3. Each end of the head 13 has a pair of set screws 29 threaded thereinto, each of which enters one of the sockets 27 to engage and hold in adjusted position the tooth 28 therein.

In connecting up a number of the cutters 1 the bars 4, which are apertured in each end, have each of their ends extended into the restricted portion 18 of the passage 17 through the cutter and when the apertures in the bars are aligned with the proper ones of the apertures 19 in t-he cutter head a retaining pin 30 is passed through the aperture, as illustrated in Figure These pins may in turn have retaining pins 31 passed therethrough to prevent their accidental displacement.

It will be seen from the foregoing that a number of the cutter units 1 may be readily strung together in such a manner that they may be readily drawn across a body of coal, as illustrated in Figure 1, and it will also be seen that by regulating the posit-ions of the cutter teeth 28 in their respective sockets the width of the cut made in the coal may be regulated.

By moving the connections between the pulley blocks 8 and the posts 6 vertically, as the cuts are made through the coal vein in the pillar 2, a. relatively wide vein may be cut away without having to shift any of the cutting mechanism. It will thus be seen that with cutters of the character herein described assembled and employed according to the method shown and described, a single attendant may perform a cutting operation which heretofore has necessitated the attention of several workers.

Having thus described my invention, what l claim as new, is:

1. A cutter of the character described comprising a relatively long fiat body of reduced thickness through a longitudinal central area of substantial width, forming a relatively wide head longitudinally of one edge, and a longitudinally extending portion at the opposite edge of the same thickness as said head, said head having the longitudinal corners beveled off to provide two longitudinally extending inclined faces separated by a longitudinally extending central face, said central face having a plurality of bit sockets therein and spaced along a longitudinal center line, said inclined faces at each end of the head each having a bit socket therein extending at right angles to the inclined face through which it opens, a cutting bit in each of said bitsockets, means for securing said cutting bits in adjusted position in the sockets, link members for coupling the cutter with adjacent cutters, and means for securing an end of a link member in each end of the cutter body between the faces of the said central area.

2. A cutter of the character described comprising a relatively long flat body of reduced thickness through a longitudinal central area of substantial width, forming a relatively wide head longitudinally of one edge, and a longitudinally extending portion at the opposite edge of the same thickness as said head, said head having the longitudinal corners beveled ofi to provide two longitudinally extending inclined faces separated by a longitudinally extending central face, said central face having a plurality of bit sockets therein and spaced along a longitudinal center line, said inclined faces at each end of the head each having a bit socket therein extending at right angles to the inclined face through which it opens, a cutting bit in each of said bit sockets, said central face having a notch cut transversely thereof adjacent a bit socket therein, each notch having a face disposed obliquely to the adjacent socket and` having a tapped passage extending therethrough into the adjacent socket, a set screw threaded into each tapped passage for frictional engagement with a bit in the adjacent socket, set screws tapped into each end of the head and extending into a bit socket in an inclined face for securing a bit therein, said cutter body having a flat passage therethrough between the side faces of the reduced central area, link members for connecting the ends of the cutter with adjacent cutters, and each having one end extending into said last passage, and securing pins extending through the last mentioned passage and through the inserted link end for retaining the links in position, the ends of said pins terminating short of the planes of the side faces of the head. In testimony whereof I hereunto aiix my signature.

JOHN R'. LAWSON. 

